code: def generate_inputs(self):
      x_size = numpy.prod(self.x_shape)
      x = (
          numpy.random.permutation(numpy.arange(x_size))
          .reshape(self.x_shape)
          .astype(self.dtype)
      )
      return (x,)
  
file_path: chainer/tests/chainer_tests/functions_tests/activation_tests/test_maxout.py
imports: import unittest
  import numpy
  import chainer
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  from chainer.utils import type_check
label_desc: Use image node_id 1 for calling the TestNonparameterizedMaxout obj's underlying member method code with example usage: obj.generate_inputs() and returns: x